To evaluate the ability of optical coherence tomography angiography to detect early microvascular changes in eyes of diabetic individuals without clinical retinopathy.
Prospective observational study of 61 eyes of 39 patients with diabetes mellitus and 28 control eyes of 22 age-matched healthy subjects that received imaging using optical coherence tomography angiography between August 2014 and March 2015. Eyes with concomitant retinal, optic nerve, and vitreoretinal interface diseases and/or poor-quality images were excluded. Foveal avascular zone size and irregularity, vessel beading and tortuosity, capillary nonperfusion, and microaneurysm were evaluated.
Foveal avascular zone size measured 0.348 mm2 (0.1085–0.671) in diabetic eyes and 0.288 mm2 (0.07–0.434) in control eyes (P = 0.04). Foveal avascular zone remodeling was seen more often in diabetic than control eyes (36% and 11%, respectively; P = 0.01). Capillary nonperfusion was noted in 21% of diabetic eyes and 4% of control eyes (P = 0.03). Microaneurysms and venous beading were noted in less than 10% of both diabetic and control eyes. Both diabetic and healthy control eyes demonstrated tortuous vessels in 21% and 25% of eyes, respectively.
Optical coherence tomography angiography was able to image foveal microvascular changes that were not detected by clinical examination in diabetic eyes. Changes to the foveal avascular zone and capillary nonperfusion were more prevalent in diabetic eyes, whereas vessel tortuosity was observed with a similar frequency in normal and diabetic eyes. Optical coherence tomography angiography may be able to detect diabetic eyes at risk of developing retinopathy and to screen for diabetes quickly and noninvasively before the systemic diagnosis is made.
Optical coherence tomography angiography can detect early microvascular changes in eyes of diabetic subjects without clinical retinopathy. Foveal avascular zone enlargement and remodeling, and also capillary nonperfusion, were more prevalent in diabetic eyes than in healthy nondiabetic control eyes and were noted before microaneurysms.
*Department of Ophthalmology, New England Eye Center and Tufts Medical Center, Tufts University, Boston, MA;
†Department of Electrical Engineering and Computer Science, and Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, MA; and
‡CAPES Foundation, Ministry of Education of Brazil, Brasilia, Brazil.
Reprint requests: Nadia K. Waheed, MD, MPH, New England Eye Center at Tufts Medical Center, 260 Tremont Street, Biewend Building, 9–11th Floor, Boston, MA 02116; e-mail: email@example.com
Supported in part by the Massachusetts Lions Clubs. J. S. Duker is a consultant for and receives research support from Carl Zeiss Meditec, OptoVue, and Topcon Medical Systems Inc.; and has stock in Hemera Biosciences Inc., EyeNetra, and Ophthotech Corp. N. K. Waheed was a consultant for Iconic therapeutics, served the speaker's bureau for Thrombogenics, and receives research support from Carl Zeiss Meditec. C. R. Baumal is a consultant for Allergan and received a travel grant from Optovue.
Presented at the American Academy of Ophthalmology, November 2015, Las Vegas, Nevada.
None of the authors have any conflicting interests to disclose.